The Marvel vs. Capcom 3 roster just keeps on growing. At a New York Comic Con panel, Capcom announced the addition of Bionic Commando's Nathan Spencer (with dreadlocks and bionic arm!) and Ghosts 'N Goblins' Sir Arthur, both from the Capcom half of the fighting mash-up. In addition, Capcom revealed some alternate costumes for Spider-Man. Oh, and there's a story, too:

"Victor Von Doom has assembled the greatest villains his world has to offer. Together with the diabolical Albert Wesker, this unholy alliance will join their respective universes in an effort to conquer both. But doing so has come with a terrible price. A great and powerful threat has been awakened .... a threat that will set into motion a battle the likes of which neither world has ever seen ... a battle that threatens the fate of two worlds!"

But that's not all! This weekend will hold at least one more MvC3-related surprise. Marvel is having a panel of its own tomorrow morning at 10:45 a.m. EDT, where it will announce two more characters from its side of the game -- in addition to a brand new game. We know that one is a returning character, but one is a newcomer to games. Exciting, no? We're planning on live-blogging the event, so stay tuned!